Ionizing Radiation and Toxic Chemical Mixtures

Ionizing radiation is an effective killer of microorganisms and cancerous tissues. Accordingly, it is used to sterilize medical devices, to irradiate food, and to treat tumors. Ionizing radiation includes emissions from radioisotopes and x-rays. X-rays have numerous beneficial uses and are tolerated well by humans in small doses. It is well known that exposure to excessive quantities of ionizing radiation can induce mutations and carcinogenesis and, in extreme cases, cause death. 

Exposure to ionizing radiation and some chemicals induce unanticipated effects. The following are examples of such interactions. 

Simultaneous exposure to 1,2-dibromoethane and low doses of x-rays has been shown to induce somatic mutations. The authors of the study ascribe this synergistic effect as due to single strand legions in the DNA.E1 

Temozolomide, a chemotherapeutic drug used to treat cancerous human brain tumors, enhances radiation response in human glioblastoma cells 

A synergistic antitumor effect was observed in human chronic lymphocytic leukemia cells when treated with radiation and a combination of 2 -deoxycoformycin and deoxyadenosine. The effects noted were greater than the predicted additive ones. Synergism was enhanced by increasing radiation or by raising the concentration of deoxyadenosine. The authors of the study conclude that the combination of 2 -deoxycoformycin and deoxyadenosine acts as a radiosensitizer.  

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